curlftpfs/cache.c

553 lines
15 KiB
C

/*
Caching file system proxy
Copyright (C) 2004 Miklos Szeredi <miklos@szeredi.hu>
This program can be distributed under the terms of the GNU GPL.
See the file COPYING.
*/
#include "cache.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <glib.h>
#include <pthread.h>
struct cache {
int on;
unsigned stat_timeout;
unsigned dir_timeout;
unsigned link_timeout;
struct fuse_cache_operations *next_oper;
GHashTable *table;
pthread_mutex_t lock;
time_t last_cleaned;
};
static struct cache cache;
struct node {
struct stat stat;
int not_found;
time_t stat_valid;
char **dir;
time_t dir_valid;
char *link;
time_t link_valid;
time_t valid;
};
struct fuse_cache_dirhandle {
const char *path;
fuse_dirh_t h;
fuse_dirfil_t filler;
GPtrArray *dir;
};
static void free_node(gpointer node_)
{
struct node *node = (struct node *) node_;
g_strfreev(node->dir);
g_free(node);
}
static int cache_clean_entry(void *key_, struct node *node, time_t *now)
{
(void) key_;
if (*now > node->valid)
return TRUE;
else
return FALSE;
}
static void cache_clean(void)
{
time_t now = time(NULL);
if (now > cache.last_cleaned + MIN_CACHE_CLEAN_INTERVAL &&
(g_hash_table_size(cache.table) > MAX_CACHE_SIZE ||
now > cache.last_cleaned + CACHE_CLEAN_INTERVAL)) {
g_hash_table_foreach_remove(cache.table,
(GHRFunc) cache_clean_entry, &now);
cache.last_cleaned = now;
}
}
static struct node *cache_lookup(const char *path)
{
return (struct node *) g_hash_table_lookup(cache.table, path);
}
static void cache_purge(const char *path)
{
g_hash_table_remove(cache.table, path);
}
static void cache_purge_parent(const char *path)
{
const char *s = strrchr(path, '/');
if (s) {
if (s == path)
g_hash_table_remove(cache.table, "/");
else {
char *parent = g_strndup(path, s - path);
cache_purge(parent);
g_free(parent);
}
}
}
static void cache_invalidate(const char *path)
{
pthread_mutex_lock(&cache.lock);
cache_purge(path);
pthread_mutex_unlock(&cache.lock);
}
static void cache_invalidate_dir(const char *path)
{
pthread_mutex_lock(&cache.lock);
cache_purge(path);
cache_purge_parent(path);
pthread_mutex_unlock(&cache.lock);
}
static void cache_do_rename(const char *from, const char *to)
{
pthread_mutex_lock(&cache.lock);
cache_purge(from);
cache_purge(to);
cache_purge_parent(from);
cache_purge_parent(to);
pthread_mutex_unlock(&cache.lock);
}
static struct node *cache_get(const char *path)
{
struct node *node = cache_lookup(path);
if (node == NULL) {
char *pathcopy = g_strdup(path);
node = g_new0(struct node, 1);
g_hash_table_insert(cache.table, pathcopy, node);
}
return node;
}
void cache_add_attr(const char *path, const struct stat *stbuf)
{
struct node *node;
time_t now;
pthread_mutex_lock(&cache.lock);
node = cache_get(path);
now = time(NULL);
if (stbuf) {
node->stat = *stbuf;
node->not_found = 0;
} else {
node->not_found = 1;
}
node->stat_valid = time(NULL) + cache.stat_timeout;
if (node->stat_valid > node->valid)
node->valid = node->stat_valid;
cache_clean();
pthread_mutex_unlock(&cache.lock);
}
void cache_add_dir(const char *path, char **dir)
{
struct node *node;
time_t now;
pthread_mutex_lock(&cache.lock);
node = cache_get(path);
now = time(NULL);
g_strfreev(node->dir);
node->dir = dir;
node->not_found = 0;
node->dir_valid = time(NULL) + cache.dir_timeout;
if (node->dir_valid > node->valid)
node->valid = node->dir_valid;
cache_clean();
pthread_mutex_unlock(&cache.lock);
}
static size_t my_strnlen(const char *s, size_t maxsize)
{
const char *p;
for (p = s; maxsize && *p; maxsize--, p++);
return p - s;
}
void cache_add_link(const char *path, const char *link, size_t size)
{
struct node *node;
time_t now;
pthread_mutex_lock(&cache.lock);
node = cache_get(path);
now = time(NULL);
g_free(node->link);
node->link = g_strndup(link, my_strnlen(link, size-1));
node->not_found = 0;
node->link_valid = time(NULL) + cache.link_timeout;
if (node->link_valid > node->valid)
node->valid = node->link_valid;
cache_clean();
pthread_mutex_unlock(&cache.lock);
}
static int cache_get_attr(const char *path, struct stat *stbuf)
{
struct node *node;
int err = -EAGAIN;
pthread_mutex_lock(&cache.lock);
node = cache_lookup(path);
if (node != NULL) {
time_t now = time(NULL);
if (node->stat_valid - now >= 0) {
if (node->not_found) {
err = -ENOENT;
} else {
*stbuf = node->stat;
err = 0;
}
}
}
pthread_mutex_unlock(&cache.lock);
return err;
}
static int cache_getattr(const char *path, struct stat *stbuf)
{
int err = cache_get_attr(path, stbuf);
if (err == -EAGAIN) {
err = cache.next_oper->oper.getattr(path, stbuf);
if (!err)
cache_add_attr(path, stbuf);
else if (err == -ENOENT)
cache_add_attr(path, NULL);
}
return err;
}
static int cache_readlink(const char *path, char *buf, size_t size)
{
struct node *node;
int err;
pthread_mutex_lock(&cache.lock);
node = cache_lookup(path);
if (node != NULL) {
time_t now = time(NULL);
if (node->link_valid - now >= 0) {
strncpy(buf, node->link, size-1);
buf[size-1] = '\0';
pthread_mutex_unlock(&cache.lock);
return 0;
}
}
pthread_mutex_unlock(&cache.lock);
err = cache.next_oper->oper.readlink(path, buf, size);
if (!err)
cache_add_link(path, buf, size);
return err;
}
static int cache_dirfill(fuse_cache_dirh_t ch, const char *name,
const struct stat *stbuf)
{
int err = ch->filler(ch->h, name, 0, 0);
if (!err) {
char *fullpath;
g_ptr_array_add(ch->dir, g_strdup(name));
fullpath = g_strdup_printf("%s/%s", !ch->path[1] ? "" : ch->path, name);
cache_add_attr(fullpath, stbuf);
g_free(fullpath);
}
return err;
}
static int cache_getdir(const char *path, fuse_dirh_t h, fuse_dirfil_t filler)
{
struct fuse_cache_dirhandle ch;
int err;
char **dir;
struct node *node;
pthread_mutex_lock(&cache.lock);
node = cache_lookup(path);
if (node != NULL && node->dir != NULL) {
time_t now = time(NULL);
if (node->dir_valid - now >= 0) {
for(dir = node->dir; *dir != NULL; dir++)
filler(h, *dir, 0, 0);
pthread_mutex_unlock(&cache.lock);
return 0;
}
}
pthread_mutex_unlock(&cache.lock);
ch.path = path;
ch.h = h;
ch.filler = filler;
ch.dir = g_ptr_array_new();
err = cache.next_oper->cache_getdir(path, &ch, cache_dirfill);
g_ptr_array_add(ch.dir, NULL);
dir = (char **) ch.dir->pdata;
if (!err)
cache_add_dir(path, dir);
else
g_strfreev(dir);
g_ptr_array_free(ch.dir, FALSE);
return err;
}
static int cache_unity_dirfill(fuse_cache_dirh_t ch, const char *name,
const struct stat *stbuf)
{
(void) stbuf;
return ch->filler(ch->h, name, 0, 0);
}
static int cache_unity_getdir(const char *path, fuse_dirh_t h,
fuse_dirfil_t filler)
{
struct fuse_cache_dirhandle ch;
ch.h = h;
ch.filler = filler;
return cache.next_oper->cache_getdir(path, &ch, cache_unity_dirfill);
}
static int cache_mknod(const char *path, mode_t mode, dev_t rdev)
{
int err = cache.next_oper->oper.mknod(path, mode, rdev);
if (!err)
cache_invalidate_dir(path);
return err;
}
static int cache_mkdir(const char *path, mode_t mode)
{
int err = cache.next_oper->oper.mkdir(path, mode);
if (!err)
cache_invalidate_dir(path);
return err;
}
static int cache_unlink(const char *path)
{
int err = cache.next_oper->oper.unlink(path);
if (!err)
cache_invalidate_dir(path);
return err;
}
static int cache_rmdir(const char *path)
{
int err = cache.next_oper->oper.rmdir(path);
if (!err)
cache_invalidate_dir(path);
return err;
}
static int cache_symlink(const char *from, const char *to)
{
int err = cache.next_oper->oper.symlink(from, to);
if (!err)
cache_invalidate_dir(to);
return err;
}
static int cache_rename(const char *from, const char *to)
{
int err = cache.next_oper->oper.rename(from, to);
if (!err)
cache_do_rename(from, to);
return err;
}
static int cache_link(const char *from, const char *to)
{
int err = cache.next_oper->oper.link(from, to);
if (!err) {
cache_invalidate(from);
cache_invalidate_dir(to);
}
return err;
}
static int cache_chmod(const char *path, mode_t mode)
{
int err = cache.next_oper->oper.chmod(path, mode);
if (!err)
cache_invalidate(path);
return err;
}
static int cache_chown(const char *path, uid_t uid, gid_t gid)
{
int err = cache.next_oper->oper.chown(path, uid, gid);
if (!err)
cache_invalidate(path);
return err;
}
static int cache_truncate(const char *path, off_t size)
{
int err = cache.next_oper->oper.truncate(path, size);
if (!err)
cache_invalidate(path);
return err;
}
static int cache_utime(const char *path, struct utimbuf *buf)
{
int err = cache.next_oper->oper.utime(path, buf);
if (!err)
cache_invalidate(path);
return err;
}
static int cache_write(const char *path, const char *buf, size_t size,
off_t offset, struct fuse_file_info *fi)
{
int res = cache.next_oper->oper.write(path, buf, size, offset, fi);
if (res >= 0)
cache_invalidate(path);
return res;
}
#if FUSE_VERSION >= 25
static int cache_create(const char *path, mode_t mode,
struct fuse_file_info *fi)
{
int err = cache.next_oper->oper.create(path, mode, fi);
if (!err)
cache_invalidate_dir(path);
return err;
}
static int cache_ftruncate(const char *path, off_t size,
struct fuse_file_info *fi)
{
int err = cache.next_oper->oper.ftruncate(path, size, fi);
if (!err)
cache_invalidate(path);
return err;
}
static int cache_fgetattr(const char *path, struct stat *stbuf,
struct fuse_file_info *fi)
{
int err = cache_get_attr(path, stbuf);
if (err == -EAGAIN) {
err = cache.next_oper->oper.fgetattr(path, stbuf, fi);
if (!err)
cache_add_attr(path, stbuf);
else if (err == -ENOENT)
cache_add_attr(path, NULL);
}
return err;
}
#endif
static void cache_unity_fill(struct fuse_cache_operations *oper,
struct fuse_operations *cache_oper)
{
#if FUSE_VERSION >= 23
cache_oper->init = oper->oper.init;
#endif
cache_oper->getattr = oper->oper.getattr;
cache_oper->readlink = oper->oper.readlink;
cache_oper->getdir = cache_unity_getdir;
cache_oper->mknod = oper->oper.mknod;
cache_oper->mkdir = oper->oper.mkdir;
cache_oper->symlink = oper->oper.symlink;
cache_oper->unlink = oper->oper.unlink;
cache_oper->rmdir = oper->oper.rmdir;
cache_oper->rename = oper->oper.rename;
cache_oper->link = oper->oper.link;
cache_oper->chmod = oper->oper.chmod;
cache_oper->chown = oper->oper.chown;
cache_oper->truncate = oper->oper.truncate;
cache_oper->utime = oper->oper.utime;
cache_oper->open = oper->oper.open;
cache_oper->read = oper->oper.read;
cache_oper->write = oper->oper.write;
cache_oper->flush = oper->oper.flush;
cache_oper->release = oper->oper.release;
cache_oper->fsync = oper->oper.fsync;
cache_oper->statfs = oper->oper.statfs;
cache_oper->setxattr = oper->oper.setxattr;
cache_oper->getxattr = oper->oper.getxattr;
cache_oper->listxattr = oper->oper.listxattr;
cache_oper->removexattr = oper->oper.removexattr;
#if FUSE_VERSION >= 25
cache_oper->create = oper->oper.create;
cache_oper->ftruncate = oper->oper.ftruncate;
cache_oper->fgetattr = oper->oper.fgetattr;
#endif
}
struct fuse_operations *cache_init(struct fuse_cache_operations *oper)
{
static struct fuse_operations cache_oper;
cache.next_oper = oper;
cache_unity_fill(oper, &cache_oper);
if (cache.on) {
cache_oper.getattr = oper->oper.getattr ? cache_getattr : NULL;
cache_oper.readlink = oper->oper.readlink ? cache_readlink : NULL;
cache_oper.getdir = oper->cache_getdir ? cache_getdir : NULL;
cache_oper.mknod = oper->oper.mknod ? cache_mknod : NULL;
cache_oper.mkdir = oper->oper.mkdir ? cache_mkdir : NULL;
cache_oper.symlink = oper->oper.symlink ? cache_symlink : NULL;
cache_oper.unlink = oper->oper.unlink ? cache_unlink : NULL;
cache_oper.rmdir = oper->oper.rmdir ? cache_rmdir : NULL;
cache_oper.rename = oper->oper.rename ? cache_rename : NULL;
cache_oper.link = oper->oper.link ? cache_link : NULL;
cache_oper.chmod = oper->oper.chmod ? cache_chmod : NULL;
cache_oper.chown = oper->oper.chown ? cache_chown : NULL;
cache_oper.truncate = oper->oper.truncate ? cache_truncate : NULL;
cache_oper.utime = oper->oper.utime ? cache_utime : NULL;
cache_oper.write = oper->oper.write ? cache_write : NULL;
#if FUSE_VERSION >= 25
cache_oper.create = oper->oper.create ? cache_create : NULL;
cache_oper.ftruncate = oper->oper.ftruncate ? cache_ftruncate : NULL;
cache_oper.fgetattr = oper->oper.fgetattr ? cache_fgetattr : NULL;
#endif
pthread_mutex_init(&cache.lock, NULL);
cache.table = g_hash_table_new_full(g_str_hash, g_str_equal, g_free,
free_node);
if (cache.table == NULL) {
fprintf(stderr, "failed to create cache\n");
return NULL;
}
}
return &cache_oper;
}
static const struct fuse_opt cache_opts[] = {
{ "cache=yes", offsetof(struct cache, on), 1 },
{ "cache=no", offsetof(struct cache, on), 0 },
{ "cache_timeout=%u", offsetof(struct cache, stat_timeout), 0 },
{ "cache_timeout=%u", offsetof(struct cache, dir_timeout), 0 },
{ "cache_timeout=%u", offsetof(struct cache, link_timeout), 0 },
{ "cache_stat_timeout=%u", offsetof(struct cache, stat_timeout), 0 },
{ "cache_dir_timeout=%u", offsetof(struct cache, dir_timeout), 0 },
{ "cache_link_timeout=%u", offsetof(struct cache, link_timeout), 0 },
FUSE_OPT_END
};
int cache_parse_options(struct fuse_args *args)
{
cache.stat_timeout = DEFAULT_CACHE_TIMEOUT;
cache.dir_timeout = DEFAULT_CACHE_TIMEOUT;
cache.link_timeout = DEFAULT_CACHE_TIMEOUT;
cache.on = 1;
return fuse_opt_parse(args, &cache, cache_opts, NULL);
}